The present invention relates to a method for actuating an electrically controllable reducing agent dosing valve which is arranged on an exhaust system of an internal combustion engine, has an injection opening projecting into the exhaust system, and has a feed connector, which feed connector is hydraulically connected by means of a feed line to a pump which generates an injection pressure at the feed connector, having a control unit which is connected to a control connector of the reducing agent dosing valve and which actuates the reducing agent dosing valve with actuation signals, to which the reducing agent dosing valve reacts with an opening action which takes place as a result of hydraulic connection of the feed connector to the injection opening, wherein the actuation signals are formed in a manner dependent on a reducing agent pressure prevailing at the pump-side end of the feed line. A method of said type serves for the actuation of an electrically controllable reducing agent dosing valve which is arranged on an exhaust system of an internal combustion engine, has an injection opening projecting into the exhaust system, and has a feed connector. The feed connector is hydraulically connected by means of a feed line to a pump which generates an injection pressure at the feed connector. A control unit is connected to a control connector of the reducing agent dosing valve and actuates the reducing agent dosing valve with actuation signals, to which the reducing agent dosing valve reacts with an opening action which takes place as a result of a hydraulic connection of the feed connector to the injection opening. The actuation signals are formed in a manner dependent on a reducing agent pressure prevailing at the pump-side end of the feed line.
A method of said type and a device of said type are known from DE 10 2007 017 459. In known reducing agent dosing systems, the reducing agent quantity for injection is controlled by means of the actuation duration with opening action and/or opening frequency of the reducing agent dosing valve. In part, in the formation of the actuation signals, the actuation duration is formed in a manner dependent on a pressure instantaneously measured in the reducing agent dosing system, and in part, to form the actuation signals, use is also made merely of a nominal pressure, which prevails in the reducing agent dosing system and which is predefined for example by a pressure-limiting valve. The formation of the actuation signals is performed with the aim of covering the reducing agent demand of an exhaust-gas purification system, for example of an SCR system. The formation of the actuation signals is therefore performed for example in a manner dependent on the mass flow and the composition of the exhaust gas for purification. In the known systems, deviations of the actually dosed reducing agent quantity with respect to the reducing agent quantity that is intended to be injected with determined actuation signals arise. Such deviations can impair the function of the exhaust-gas purification system.